1. Field of the Invention
The present invention relates to apparatus and method for in-situ calibration of a vacuum gauge by absolute method and comparison method, and more particularly, to apparatus and method for in-situ calibration of a vacuum gauge by absolute method and comparison method, which can carry out absolute calibration using a static type standard for measuring pressures of vacuum chambers by expanding and moving gas to the vacuum chambers of different volumes in order and comparison calibration of vacuum gauges in a range of 1 mPa˜1 kPa in an in-situ state without movement of the vacuum gauges according to a method for controlling gas flow through an orifice using a calibrated standard vacuum gauge.
2. Background Art
In general, till now, calibrations by absolute method and comparison method have been carried out by different apparatuses since they could be carried out by the different apparatuses. So, the necessity of an apparatus for reducing a calibration period of time and improving calibration efficiency to economically and efficiently calibrate a vacuum gauge has come to the front.